CMDRT - Certified Medical Device Reprocessing Technician High-Level Disinfection Questions and Answers — Questions and Answers
Question 1: An MDRT is preparing to use a basin of Ortho-phthalaldehyde (OPA) for manual high-level disinfection. The Minimum Effective Concentration (MEC) test strip fails to show a passing result. What is the correct immediate action?
- Record the failure and proceed with the disinfection, but double the soak time.
- Add a small amount of new OPA concentrate to the basin to increase its strength.
- Discard the entire basin of solution and prepare a fresh batch, verifying it with a new MEC test. (Correct answer)
- Use the solution for non-critical items only and prepare a new batch later.
Correct answer: Discard the entire basin of solution and prepare a fresh batch, verifying it with a new MEC test.
A failed Minimum Effective Concentration (MEC) test indicates that the disinfectant solution has fallen below the required potency to achieve high-level disinfection. [5] Using the solution would be ineffective and unsafe. The only correct procedure is to discard the failed solution and replace it with a fresh batch that has been verified with a passing MEC test before use.
Question 2: What is the primary purpose of performing a thorough final rinse with sterile, deionized, or filtered water after a device has completed its required soak time in a high-level disinfectant?
- To remove residual toxic chemical disinfectant from the device. (Correct answer)
- To activate the biocidal properties of the disinfectant just before storage.
- To cool the device to a safe temperature for handling and storage.
- To neutralize the disinfectant in the basin, making it safe for disposal.
Correct answer: To remove residual toxic chemical disinfectant from the device.
High-level disinfectants are toxic chemicals that can cause serious irritation or chemical burns to patient tissue. [11, 12] A thorough rinse with high-quality water is a critical step to remove all chemical residues, ensuring the device is safe for patient contact. [6]
Question 3: Which of the following are critical parameters that must be monitored and documented for every manual high-level disinfection cycle to ensure its effectiveness?
- The ambient room humidity and air exchange rate.
- The pH level and specific gravity of the disinfectant.
- The date the disinfectant bottle was first opened.
- The immersion time and the temperature of the solution. (Correct answer)
Correct answer: The immersion time and the temperature of the solution.
For a manual high-level disinfection process to be effective, the device must be fully immersed in the solution for a specific amount of time at a specific temperature, as defined by the manufacturer's instructions for use. [3, 26] These parameters directly impact the disinfectant's ability to kill microorganisms and must be carefully controlled and documented for quality assurance and traceability.
Question 4: A reusable flexible laryngoscope, which contacts the mucous membranes of the throat, is sent to the MDRD. According to the Spaulding Classification system, what is the minimum required level of reprocessing for this device?
- Cleaning with soap and water only.
- Low-Level Disinfection.
- High-Level Disinfection. (Correct answer)
- Sterilization.
Correct answer: High-Level Disinfection.
The Spaulding Classification categorizes medical devices based on infection risk. Because a flexible laryngoscope comes into contact with mucous membranes, it is classified as a semi-critical device. [15, 22] Semi-critical devices require, at a minimum, High-Level Disinfection to eliminate all microorganisms except for large numbers of bacterial spores. Sterilization is preferred if the device can withstand it, but HLD is the minimum acceptable standard. [19]
Question 5: Ortho-phthalaldehyde (OPA) is a common high-level disinfectant. What is a key characteristic of OPA that reprocessing technicians must be aware of to ensure both safety and quality?
- It requires mixing with a powdered activator before each use.
- It will stain any residual protein (e.g., blood, tissue) on instruments a gray/blue color. [1, 2] (Correct answer)
- It is highly corrosive to stainless steel and must be rinsed off immediately.
- It must be heated to above 50°C (122°F) to be effective.
Correct answer: It will stain any residual protein (e.g., blood, tissue) on instruments a gray/blue color. [1, 2]
A primary characteristic of OPA is its ability to stain proteins gray or blue. [1, 4] This serves as a visual indicator that pre-cleaning may have been inadequate. It also means that OPA can stain unprotected skin, necessitating the use of appropriate PPE.
Question 6: When using an Automated Endoscope Reprocessor (AER) for high-level disinfection, which of the following sets of tasks must the technician perform *before* loading the endoscope into the machine?
- Packaging the endoscope in a peel pouch and adding a chemical indicator.
- Drying the channels with compressed air and documenting the cycle parameters.
- Point-of-use pre-cleaning, leak testing, and thorough manual cleaning. (Correct answer)
- Testing the MEC of the rinse water and initiating the thermal disinfection phase.
Correct answer: Point-of-use pre-cleaning, leak testing, and thorough manual cleaning.
An AER automates the high-level disinfection, rinsing, and drying stages, but it does not replace the essential manual preparation steps. [18, 24] Meticulous manual cleaning is the most critical step in the entire process to remove bioburden. [24] Leak testing is also performed before immersion to prevent costly damage to the endoscope. [5] If it is not clean, it cannot be high-level disinfected.
CMDRT - Certified Medical Device Reprocessing Technician High-Level Disinfection Questions and Answers
An MDRT is preparing to use a basin of Ortho-phthalaldehyde (OPA) for manual high-level disinfection.
The Minimum Effective Concentration (MEC) test strip fails to show a passing result.
What is the correct immediate action?